An ultra-thin motor structure including a stator assembly and a rotator assembly is provided. The stator assembly includes at least one bearing with a bore, a base, and a winding plate. The base has a protruding portion and a deck disposed in the protruding portion. The winding plate is stacked on the deck, and includes a plurality of coils formed by an electroforming process or etching process. Furthermore, the rotator assembly is disposed on the stator assembly, and includes a spindle, a top cover, and a permanent magnet ring. The spindle is fixed in the bore of the bearing, and the permanent magnet ring is disposed on the winding plate and supports the top cover thereon. Thereby, the ultra-thin motor structure can enhance the assembly and mass-production of the motor, and satisfy demands for thinning and performance of the motor.